I'd imagine this might get moved to a different section --
Sort of depends on what you prefer. For me, the Samplitude / Sequoia family are the stuff. Others prefer WaveLab or something along those lines. I use Samplitude for the object-based editing factor (along with the normal sort of mastering must-haves like assembly, DDP export, RedBook authoring, etc.). I'm sort of based in hardware, but the stock plugs in Samplitude are quite good if you're working digitally.